1. Field of the Invention
The present invention relates to a digital broadcast receiver and a control method thereof.
2. Description of the Related Art
As a television broadcast shifts from analog to digital, kinds of broadcast also diversify, and an HD (High Definition) broadcast by using one channel of band or an SD (Standard Definition) broadcast by dividing one channel of band into plural channels and using the channels is broadcast at any time. In that case, a broadcast to be received is determined by specifying a main channel indicating a broadcast station and subchannels indicating broadcast programs. Then, when the HD broadcast is completed and switches to the SD broadcast with the same channel, it becomes necessary for a user to specify a subchannel of the SD broadcast naturally.
As this specifying method, a digital broadcast receiver and a control method thereof in which switching to a predetermined subchannel preset by a maker or a user is performed in the case of switching from a one-channel broadcast such as an HD broadcast to a multi-channel broadcast such as an SD broadcast are disclosed in JP-A-11-355225.
However, in the digital broadcast receiver and the control method described in JP-A-11-355225, switching to the preset predetermined subchannel is automatically performed in the case of switching from the one-channel broadcast to the multi-channel broadcast, but a broadcast breaks when there is no broadcast of the predetermined subchannel.
Also, even when a predetermined subchannel exists and switching can be automatically performed in the case of switching from the one-channel broadcast to the multi-channel broadcast, a broadcast breaks when a broadcast of the predetermined subchannel is then completed and it becomes a broadcast of only subchannels of other numbers. Similarly, the case of switching from the multi-channel broadcast to the one-channel broadcast is not described, and when a subchannel of the switched one-channel broadcast is not a predetermined subchannel preset, a broadcast breaks. In such a case, a user must again select the subchannel and usability was bad.